Jean Hasse was born in Cleveland, Ohio, USA, 1958, and graduated from Oberlin College Conservatory, Ohio, specialising in piano, conducting and instrumental music education (BM, 1981); she then did graduate work and teaching at Cleveland State University. A varied career as a teacher, multi-instrumentalist, concert producer, music copyist, editor and publisher has included managing Margun Music (then owned by Gunther Schuller) and acting as the US and Canadian Representative for Faber Music Ltd. London, as well as forming her own publishing company, Visible Music, in 1987. While living in Boston, Jean was also a member of the popular music ensemble, The Composers in Red Sneakers. She has had several composing residency fellowships at the MacDowell Colony (NH) and the Millay Colony for the Arts (NY) and has received commissions from many solo performers and chamber ensembles in the US and UK. She moved to England in December 1994.
Jean holds two degrees from the University of Bristol: MA (Composition for Film and Television, 2006) and MMus (Original Compositions for Silent Films, 2016). From 2006-2015 she taught in the University of Bristol's Department of Music: Acoustic Composition (2006-2008) and as the Course Tutor for the MA in Composition for Film and Television (2008-2015).

Jean composes for films, silent films, videos and special events, along with new concert music pieces. Her twenty silent film scores to date began with Faust (1926), performed in October 2007 by a chamber orchestra in Bristol and at London's Barbican Centre. Four silent film scores for quartet (violin, trumpet, sax, piano) include Ghosts Before Breakfast (1928) and The Fall of the House of Usher (1928). As a piano accompanist, original scores include Mabel's Dramatic Career (1913), premiered at the National Film Theatre, London, and The Rat (1925), for piano, clarinet and accordion, played at Bristol’s Arnolfini. In 2009 Jean accompanied several silent films at an international conference on Colour Film and Restoration in Bristol. In January 2014 she performed a new score to Richard Wagner (1913) at the Barbican Centre. Ensemble scores from 2016-17 include The Devilish Tenant (1909), Arthème Swallows his Clarinet (1912) and The (?) Motorist (1906) for wind ensemble.

Other composing projects include the television documentaries, Rise of the Warrior Apes (2016, Discovery Channel) (with William Goodchild) and Autism: Coming of Age (2010, American Public Television) (with Marty Fegy), as well as music for a short film on India, an hour-long film about Japan, three animation films (DVD + childrens' books), and the film, So the Wind Won‘t Blow it All Away, (1999), based on a Richard Brautigan story, shown at festivals in the US and Europe. Jean has also composed music for website podcasts and screencasts, a theatre production, and music soundscapes for science festivals and art exhibits.

As a music copyist, proofreader and editor Jean has worked for several publishing companies and for dozens of composers, including John Williams, Ornette Coleman and Paul McCartney. She did music score preparation work for the UK films, The Killing of John Lennon and Eliminate: Archie Cookson, for which she also conducted at the recording session. In recent years Jean has assisted composer William Goodchild with a number of scoring projects.

Hasse's concert music has been heard throughout the United States and Europe, in Canada, Japan and Australia, with performances at venues including the Tanglewood Music Center, Hollywood Bowl, Carnegie Hall, Chicago's Orchestra Hall, London's South Bank Centre, Barbican Centre, Wigmore Hall, the British Museum, Mexico City's Museo Tamayo, St Paul's Cathedral, St George's Hall Bristol, and at numerous festivals.

Recordings include the CD, kinkh (1999), with a large portion of Jean’s piano music, Pulling (flutes) and After Earle (percussion). Other pieces for piano, as well as piano quartet and choir, have been released on other CD labels. From 2001-03 she composed original ring tone melodies for mobile phones, beginning with the Internet company iobox, which led to appearances on television and radio.